Provided by: libparse-fixedlength-perl_5.39-2_all bug


       Parse::FixedLength - parse an ascii string containing fixed length fields into component


           use Parse::FixedLength qw(subclassed parsers);

           $parser = Parse::FixedLength->new(\@format);
           $parser = Parse::FixedLength->new(\@format, \%parameters);
           $parser = Parse::FixedLength->new($format);
           $parser = Parse::FixedLength->new($format, \%parameters);

           $hash_ref = $parser->parse($data);
           $data = $parser->pack($hash_ref);

           $converter = $parser1->converter($parser2);
           $converter = $parser1->converter($parser2, \%mappings);
           $converter = $parser1->converter($parser2, \@mappings);
           $converter = $parser1->converter($parser2, \%mappings, \%defaults);
           $converter = $parser1->converter($parser2, \@maps, \%dflts, \%parms);

           $data_out = $converter->convert($data_in);


       The "Parse::FixedLength" module facilitates the process of breaking a string into its
       fixed-length components. Sure, it's a glorified (and in some ways more limited) substitute
       for the perl functions pack and unpack, but it's my belief that this module helps in the
       maintainability of working with fixed length formats as the number of fields in a format


        $parser = Parse::FixedLength->new(\@format)
        $parser = Parse::FixedLength->new(\@format, \%parameters)
        $parser = Parse::FixedLength->new($format)
        $parser = Parse::FixedLength->new($format, \%parameters)

       If the format argument is a string, then new will attempt to return the result of calling
       the new method for "Parse::FixedLength::$format". You can include the '$format' in the
       import list of the 'use Parse::FixedLength' statement if you want to require the format at
       compile time (See EXAMPLES).

       You can use ':all' as an argument in the import list, e.g., 'use Parse::Length qw(:all)',
       to require all available Parse::FixedLength::* modules, but obviously you can't use ':all'
       as a format argument in new().

       Otherwise the format must be an array reference of field names and lengths as either
       alternating elements, or delimited args in the same field, e.g.:

           my $parser = Parse::FixedLength->new([
               first_name => 10,
               last_name  => 10,
               address    => 20,


           my $parser = Parse::FixedLength->new([qw(

       If the first format is chosen, then no delimiter characters may appear in the field names
       (see delim option below).

       To right justify a field (during the 'pack' method), an "R" may be appended to the length
       of the field followed by (optionally) the character to pad the string with (if no
       character follows the "R", then a space is assumed). This is somewhat inefficient, so its
       only recommended if actually necessary to preserve the format during operations such as
       math or converting format lengths. If its not needed but you'd like to specify it anyway
       for documentation purposes, you can use the no_justify option below. Also, it does change
       the data in the hash ref argument.

       New (and barely tested): The length of the field may also be any valid format string for
       the perl functions pack/unpack which would return a single element.  E.g., this is valid:

           my $parser = Parse::FixedLength->new([qw(

       But this is not valid since 'flags' would return 2 elements:

           my $parser = Parse::FixedLength->new([qw(

       If a format without a known fixed length is used, then the length method, and start and
       end positions in the format should not be used.

       The optional second argument to new is a hash ref which may contain any of the following

           The delimiter used to separate the name and length in the format array. If another
           delimiter follows the length then the next two fields are assumed to be start and end
           position, and after that any 'extra' fields are ignored.  The package variable DELIM
           may also be used.  (default: ":")

           A hash reference to parse the data into. Also, if no argument is passed to the pack
           method, the default hash reference used to pack the data into a fixed length string.

           Do not bless the hash ref returned from the parse method into a Hash-As-Object
           package.  (default: false)

           This option ignores any lengths supplied in the format argument (or allows having no
           length args in the format), and sets the lengths for all the fields to this value. As
           well as the obvious case where all formats are the same length, this can help
           facilitate converting from a non-fixed length format (where you just have field names)
           to a fixed-length format.  (default: false)

           This option controls the behavior of new() when duplicate field names are found. By
           default a fatal error will be generated if duplicate field names are found. If you
           have, e.g., some unused filler fields, then as the value to this option, you can
           either supply an arrayref containing valid duplicate names or a simple true value to
           accept all duplicate values. If there is more than one duplicate field, then when
           parsed, they will be renamed '<name>_1', '<name>_2', etc.  (default: false)

           If true, preserve trailing spaces during parse.  (default: false)

           If true, ignore the "R" format option during pack.  (default: false)

           By default, if two fields exist after the length argument in the format (delimited by
           whatever delimiter is set), then they are assumed to be the start and end position
           (starting at 1), of the field, and these fields are validated to be correct, and a
           fatal error will be generated if they are not correct.  If this option is true, then
           the start and end are not validated.  (default: false)

           If true, trim leading pad characters from fields during parse.  (default: false)

           If true, print field names and values during parsing and packing (as a quick format
           validation check). The package variable DEBUG may also be used. If a non-reference
           argument is given, output is sent to STDOUT, otherwise we assume we have a filehandle
           open for writing.  (default: false)

        $hash_ref = $parser->parse($string)
        @ary      = $parser->parse($string)

       This method takes a string and returns a hash reference of field names and values if
       called in scalar context, or just a list of the values if called in list context. The hash
       reference returned is an object, so you can either get/set values the normal way:

           $href->{key} = "value";
           print "$href->{key}\n";

       or you can use methods:

           $href->key = "value";
           print $href->key,"\n";

       For efficiency, the same hash reference is returned on each parse.  If this is not
       acceptable, look into "parse_newref" or "parse_hash".  See CAVEATS.

        %hash = $parser->parse_hash($string)

       Same as parse, but returns a hash array instead of a hash reference.

        $hash_ref = $parser->parse_newref($string)

       Same as parse, but returns a different hash reference on every call, and the reference
       returned is not an object, just a plain old hashref.

        $data = $parser->pack(\%data_to_pack);

       This method takes a hash reference of field names and values and returns a fixed length
       format output string.

       If no argument is passed, then the hash reference used in the href option of the
       constructor is used.


       This turns a hash reference into an object where the keys of the hash can be used as
       methods for accessing or setting the values of the hash. This turns the hash into a semi-
       secure hash which is a sort of combination of Hash::AsObject and Tie::SecureHash in that
       no new keys will be added to the hash if only methods are used to access the hash. Hashes
       with the same set of keys are blessed into the same package, so adding keys to one hash
       may affect the methods allowed on another hash.


       This method trims leading pad characters from the data. It is the method implicitly called
       during the parse method when the 'trim' option is set in new(). The data passed is
       modified, so there is no return value.

        $ary_ref = $parser->names;

       Return an ordered arrayref of the field names.

        $fmt_str = $parser->format_str;

       Return the format string used for unpacking.

        $tot_length   = $parser->length;
        $field_length = $parser->length($name);

       Returns the total length of all the fields, or of just one field name.  E.g.:

        # If there are no line feeds
        while (read FH, $data, $parser->length) {


       Returns the parser's format layout information in a format suitable for cutting and
       pasting into the format array argument of a Parse::FixedFormat->new() call, and includes
       the start and end positions of all the fields (starting with position 1). If a true
       argument is supplied then it will include the start and ending positions as comments.

        # Assume the parser is from the ones defined in the new() example:
        print $parser->dumper(1);

        produces for first example:
        first_name => 10, # 1-10
        last_name => 10, # 11-20
        address => 20, # 21-40

        or for the second example:
        print $parser->dumper;


        $converter = $parser1->converter($parser2, \@maps, \%dflts, \%parms);

       Returns a format converting object. $parser1 is the parsing object to convert from,
       $parser2 is the parsing object to convert to.

       By default, common field names will be mapped from one format to the other.  Fields with
       different names can be mapped from the first format to the other (or you can override the
       default) using the second argument.  The keys are the source field names and the
       corresponding values are the target field names. This argument can be a hash ref or an
       array ref since you may want to map one source field to more than one target field.

       Defaults for any field in the target format can be supplied using the third argument,
       where the keys are the field names of the target format, and the value can be a scalar
       constant, or a subroutine reference where the first argument is simply the mapped value
       (or the empty string if there was no mapping), and the second argument is the entire hash
       reference that results from parsing the data with the 'from' parser object. E.g. if you
       were mapping from a separate 'zip' and 'plus_4' field to a 'zip_plus_4' field, you could
       map 'zip' to 'zip_plus_4' and then supply as one of the key/value pairs in the 'defaults'
       hash ref the following:

        zip_plus_4 => sub { shift() . $_[0]{plus_4} }

       The fourth argument is an optional hash ref may which may contain the following:

           If true, the convert() method will return a hash reference instead of packing the data
           into an ascii string (Default: false).

        $data_out = $converter->convert($data_in);
        $data_out = $converter->convert($data_in, $no_pack);
        $data_out = $converter->convert(\%hash);
        $data_out = $converter->convert(\%hash, $no_pack);

       Converts a string or a hash reference from one fixed length format to another.  If a
       second argument is supplied, it will override the converter's no_pack option setting.


           use Parse::FixedLength;

           # Include start and end position for extra check
           # of format integrity
           my $parser = Parse::FixedLength->new([
               first_name => '10:1:10',
               last_name  => '10:11:20',
               widgets_this_month => '5R0:21:25',

           # Do a simple name casing of names
           # and print widgets projected for the year for each person
           while (<DATA>) {
               warn "No record terminator found!\n" unless chomp;
               warn "Short Record!\n" unless $parser->length == length;
               my $data = $parser->parse($_);
               # See Lingua::EN::NameCase for a real attempt at name casing
               s/(\w+)/\u\L$1/g for @$data{qw(first_name last_name)};
               $data->{widgets_this_month} *= 12;
               print $parser->pack($data), "\n";
           BOB       JONES     00024
           JOHN      SMITH     00005
           JANE      DOE       00007

           Another way if we're converting formats:

           my $parser1 = Parse::FixedLength->new([
               first_name => 10,
               last_name  => 10,
               widgets_this_month => '5R0',

           my $parser2 = Parse::FixedLength->new([qw(

           my $converter = $parser1->converter($parser2, {
               widgets_this_month => "widgets_this_year",
               seq_id => do { my $cnt = '0' x $parser2->length('seq_id');
                              sub { ++$cnt };
               widgets_this_year => sub { 12 * shift },
               country => 'USA',

           while (<DATA>) {
               warn "No record terminator found!\n" unless chomp;
               warn "Short Record!\n" unless $parser1->length == length;
               print $converter->convert($_), "\n";

   Subclassing Example
           # Must be installed as Parse/FixedLength/
           # somewhere in @INC path.
           package Parse::FixedLength::DrugCo100;

           use Parse::FixedLength;
           our @ISA = qw(Parse::FixedLength);

           sub new {
               my $proto = shift;
               my $class = ref($proto) || $proto;
               $flags = shift || {};
               die "Options arg not a hash ref"
                   unless UNIVERSAL::isa($flags,'HASH');
               $$flags{autonum} = ['filler'];
               bless $class->SUPER::new([qw(
               )], $flags), $class;

           Then in main script:

           # Import list on use statement is optional, but
           # will cause require at compile time rather than run time.
           use Parse::FixedLength qw(DrugCo100);
           my $parser = Parse::FixedLength->new('DrugCo100');

           # Or of course you could just:
           use Parse::FixedLength::DrugCo100;
           my $parser = Parse::FixedLength::Drugco100->new;


       Mentioned in the documentation for "parse", repeated here:

       For efficiency, a parser object will return the same hash reference on every call to
       parse. Therefore, any code such as this which tries to save every record will not work:

           while (<>) {
               my $href = $parser->parse($_);
               push @array, $href; # Refers to same hash every time

       and should be changed to this:

           while (<>) {
               my $href = $parser->parse_newref($_);
               push @array, $href;

       or this:

           while (<>) {
               my $href = $parser->parse($_);
               push @array, { %$href };


        Douglas Wilson <>
        original by Terrence Brannon <>


        This module is free software; you can redistribute it and/or
        modify it under the same terms as Perl itself.


       Other glorified substitutes for pack/unpack: Text::FixedLength, Data::FixedFormat,
       AnyData::Format::Fixed (although the AnyData module is part of a larger collection of
       modules which facilitates converting data between many different kinds of formats, and
       using SQL to query those data sources via DBD::AnyData).